Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f149b31124ae69f…

MALICIOUS

PDF

39.1 KB Created: 2020-08-29 06:13:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cb03d3e67f52b34a04c54920b83b7f60 SHA-1: a20b85135ff863b0ca027e3fffe5a70ac2fc055f SHA-256: 5f149b31124ae69f403635f671db8cb68e2112122b039e1512367edbf2e1bd24
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links to external PDF files, many of which are hosted on static.usrfiles.com. One of the primary links, however, points to a known malicious redirector at ttraff.ru. This suggests a link farm or SEO poisoning attack designed to direct users to malicious content. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.ru/wix?keyword=heroes+of+the+storm+stats
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/b8c837_ea1fb4191b574145802eeb00d14fb208.pdf
    • https://static.usrfiles.com/ugd/b8c837_aca25c648844406a92e44be2b257f3c1.pdf
    • https://static.usrfiles.com/ugd/b8c837_8fbb4db14bcf4200b898f6145b9b1716.pdf
    • https://static.usrfiles.com/ugd/b8c837_786b29f0b22e4a6780c170107ac82d8c.pdf
    • https://static.usrfiles.com/ugd/b8c837_3d242bff7d5f40cfa0bd56abaee3b691.pdf
    • https://static.usrfiles.com/ugd/b8c837_cb3ea54105ef4658835b9d0c8fa9d876.pdf
    • https://static.usrfiles.com/ugd/b8c837_59da4d82b3f7489ba22734dd22dd03bd.pdf
    • https://static.usrfiles.com/ugd/b8c837_5e7d034b28b7452ca751a6a9e9c3f1e1.pdf
    • https://static.usrfiles.com/ugd/b8c837_7e6b4f78c61047bbb36f3180580c07c0.pdf
    • https://cdn.shopify.com/s/files/1/0430/9801/3845/files/sowetokuvagugenoxer.pdf
    • https://cdn.shopify.com/s/files/1/0434/4188/1253/files/xedububureko.pdf
    • https://cdn.shopify.com/s/files/1/0433/7532/9441/files/design_of_liquid_propellant_rocket_engines.pdf
    • https://cdn.shopify.com/s/files/1/0432/8249/7701/files/candle_in_the_wind_piano_sheet.pdf
    • https://static.usrfiles.com/ugd/b8c837_7edd44ac085d4c6fa20bd1fb0a4a616f.pdf
    • https://static.usrfiles.com/ugd/b8c837_58ab13cd913f46148ffee3d58e94a141.pdf
    • https://static.usrfiles.com/ugd/b8c837_cae205891ee14df2a6350cbbf637fad2.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005c34.bin
19ed65fd515c737710a0b3e8ebbd2e2dbd5c273896df97fcd3da46c80549ae8f
pdf-font-stream PDF embedded font (sfnt) at offset 0x5C34 4936 bytes
font_01_sfnt_off00006cd1.bin
ddf669994b0d81f243851e246d0791b96fe2f7b57aa4eab7e5967e171b0dcdd7
pdf-font-stream PDF embedded font (sfnt) at offset 0x6CD1 10204 bytes